https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81601
--- Comment #24 from Aldy Hernandez <aldyh at gcc dot gnu.org> ---
(In reply to Jakub Jelinek from comment #23)
> What would create those BIT_FIELD_REFs so early though? They should stay as
> COMPONENT_REFs.
I thought you'd never ask... why our friend fold_truth_andor_1 :).
/* Make a mask that corresponds to both fields being compared.
Do this for both items being compared. If the operands are the
same size and the bits being compared are in the same position
then we can do this by masking both and comparing the masked
results. */
